<template>
  <div class="score-case">
    <div class="table">
      <table>
        <thead>
          <tr>
            <th>编号</th>
            <th>科目</th>
            <th>成绩</th>
            <th>考试时间</th>
            <th>操作</th>
          </tr>
        </thead>
        <tbody>
         <!-- v-for渲染结构 -->
          <tr v-for="(item, index) in list " :key="item.id">
            <!-- 插值表达 -->
            <td>{{index+1}}</td>
            <td>{{item.subject}}</td>
            <!-- :class控制样式，还可以用三元表达式操作 item.scor<60?'red':'' -->
                        <td  :class="{red:item.score<60}" >{{item.score}}</td>
            <td>{{formatDate(item.date)}}</td>
            <td><a href="#" @click.prevent='delFn(item.id)'>删除</a></td>
          </tr>
          <!-- <tr >
            <td>2</td>
            <td>数学</td>
            <td>100</td>
            <td>Tue Jun 07 2022 10:00:00 GMT+0800 (中国标准时间)</td>
            <td><a href="#">删除</a></td>
          </tr> -->
        </tbody>
        <tbody  v-show="list.length===0">
          <tr>
            <td colspan="5">
              <span class="none">暂无数据</span>
            </td>
          </tr>
        </tbody>
        <tfoot>
          <tr>
            <td colspan="5">
              <span>总分：{{sumScore}}</span>
              <span style="margin-left:50px">平均分：{{avgScore}}</span>
            </td>
          </tr>
        </tfoot>
      </table>
    </div>
    <div class="form">
      <div class="form-item">
        <div class="label">科目：</div>
        <div class="input">
          <input type="text" placeholder="请输入科目" />
        </div>
      </div>
      <div class="form-item">
        <div class="label">分数：</div>
        <div class="input">
          <input type="text" placeholder="请输入分数" />
        </div>
      </div>
      <div class="form-item">
        <div class="label"></div>
        <div class="input">
          <button class="submit" @click='submit'>添加</button>
        </div>
      </div>
    </div>
  </div>
</template>

<script>
import moment from 'moment'
export default {
  
  name: 'ScoreCase',
  data () {
    return {
      list: JSON.parse(localStorage.getItem('score-case')) || [],
      subject: '',
      score: ''
    }
  },
  methods:{
    delFn(id){
        // console.log(id);
      // 1根据ID 找到索引
      //  this.list=this.list.findIndex(item => item.id=id)
      //  this.list.splice(index, 1)


      //2通过filter匹配符合条件的为true,不符合的为fales
      this.list=(this.list.filter(item => item.id !==id))
    },
    submit(){
      //年龄取值在0-100之间
      console.log(list.score,list.subject,'==');
      
      if(this.score>=0 && this.score<=100 && this.subject){
        this.list.push({
// 设置ID名字，有内容时名字为最后一个，没有内容为1
        id: this.list.length ? this.list.at(-1).id+1 : 1,
        subject: this.subject,
        score:this.score,
        date:new Date()
      })
      // 清空
      this.subject=''
      this.score=''
      }else{
        alert('输入的不正确')
      }
      
    },
    // 设置中国时间

    formatDate(dt){
      return moment(dt).format('YYYY-MM-DD HH:mm:ss')
    }
  },
  computed:{
    // 计算总分
    sumScore(){
      return this.list.reduce((sum,item)=>sum+item.score,0)
    },
    avgScore(){//平均分，没有内容则用0表示
       return this.list.length>0? (this.sumScore/this.list.length).toFixed(2) :0
       }
  },
  // 属性监听
   watch:{
      list:{
deep: true,//代表深度监听
handler(){
  localStorage.setItem('scoer-case',JSON.stringify(this.list))
}
      }
    }
};
</script>

<style lang="less">
.score-case {
  width: 1000px;
  margin: 50px auto;
  display: flex;
  .table {
    flex: 4;
    table {
      width: 100%;
      border-spacing: 0;
      border-top: 1px solid #ccc;
      border-left: 1px solid #ccc;
      th {
        background: #f5f5f5;
      }
      tr:hover td {
        background: #f5f5f5;
      }
      td,
      th {
        border-bottom: 1px solid #ccc;
        border-right: 1px solid #ccc;
        text-align: center;
        padding: 10px;
        &.red {
          color: red;
        }
      }
    }
    .none {
      height: 100px;
      line-height: 100px;
      color: #999;
    }
  }
  .form {
    flex: 1;
    padding: 20px;
    .form-item {
      display: flex;
      margin-bottom: 20px;
      align-items: center;
    }
    .form-item .label {
      width: 60px;
      text-align: right;
      font-size: 14px;
    }
    .form-item .input {
      flex: 1;
    }
    .form-item input,
    .form-item select {
      appearance: none;
      outline: none;
      border: 1px solid #ccc;
      width: 200px;
      height: 40px;
      box-sizing: border-box;
      padding: 10px;
      color: #666;
    }
    .form-item input::placeholder {
      color: #666;
    }
    .form-item .cancel,
    .form-item .submit {
      appearance: none;
      outline: none;
      border: 1px solid #ccc;
      border-radius: 4px;
      padding: 4px 10px;
      margin-right: 10px;
      font-size: 12px;
      background: #ccc;
    }
    .form-item .submit {
      border-color: #069;
      background: #069;
      color: #fff;
    }
  }
}
</style>



